Stamped rear frame bolster

ABSTRACT

A cargo transport rear frame includes a pair of posts, an upper cross member, and a rear bolster. The posts are spaced in a width direction, and extend in a height direction. The upper cross member extends along the width between the posts. The rear bolster extends between lower ends of the posts such that the rear bolster is spaced below the upper cross member. The posts, the upper cross member, and the rear bolster bound the rear cargo opening. The rear bolster has a first side facing in a forward direction, and the rear bolster has a second side facing in a rearward direction to be exposed to a rear side of the cargo transport rear frame. The rear bolster comprises a sheet metal stamping including a base surface and a relief embossed in the rearward direction from the base surface to form a loading dock engagement feature.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.16/532,807, filed Aug. 6, 2019, which claims priority to U.S.Provisional Patent Application No. 62/715,648, filed Aug. 7, 2018, theentire contents of both of which are incorporated by reference herein.

BACKGROUND

The disclosure relates to the construction of cargo transports, such asvehicles for over-the-road freight hauling. These may include enclosedand open trailers (e.g., semi-trailers), box trucks, and vans, forexample. The disclosure further relates to rear frames thereof.

SUMMARY

In one aspect, the invention provides a cargo transport rear framedefining a rear cargo opening, the cargo transport rear frame includinga pair of posts, an upper cross member, and a rear bolster. The postsare spaced apart in a width direction, each of the pair of postsextending in a height direction. The upper cross member extends alongthe width direction between respective upper ends of the pair of posts.The rear bolster extends along the width direction between respectivelower ends of the pair of posts such that the rear bolster is spacedbelow the upper cross member in the height direction. The pair of posts,the upper cross member, and the rear bolster bound the rear cargoopening. The rear bolster has a first side facing in a forward directionthat is perpendicular to both the width and height directions, and therear bolster has a second side facing in a rearward direction to beexposed to a rear side of the cargo transport rear frame. The rearbolster comprises a sheet metal stamping including a base surface and arelief embossed in the rearward direction from the base surface to forma loading dock engagement feature.

In another aspect, the invention provides a rear bolster for a cargotransport rear frame. The rear bolster includes a base surface havinglateral outboard ends spaced in a width direction and having a top edgeand a bottom edge spaced in a height direction. A first side of the rearbolster faces in a forward direction that is perpendicular to both thewidth and height directions. A second side of the rear bolster faces ina rearward direction to be exposed to a rear side of the cargo transportrear frame having the rear bolster. A relief is embossed in the rearwarddirection from the base surface to form a loading dock engagementfeature. The rear bolster, including the embossed relief, is a sheetmetal stamping.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a rear portion of a cargo transportincluding a stamped rear bolster according to one embodiment of thepresent invention.

FIG. 2 is an end view of the stamped rear bolster.

FIG. 3 is a rear view of the stamped rear bolster.

FIG. 4 is a perspective view of the stamped rear bolster.

FIG. 5 is a front view of the stamped rear bolster prior to finalforming.

FIG. 6 is an end view of the stamped rear bolster as shown in FIG. 5 .

FIG. 7 is a cross-sectional view of the stamped rear bolster taken alongline 7-7 of FIG. 5 .

FIG. 8 is a cross-sectional view of the stamped rear bolster taken alongline 8-8 of FIG. 5 .

FIG. 9 is a perspective view of a front side of the stamped rear bolsterhaving an optional backing plate.

DETAILED DESCRIPTION

FIG. 1 illustrates a rear portion of a cargo transport such as a trailer18. For example, the cargo transport 18 can be a semi-trailer or otherover-the-road cargo hauler (e.g., for attachment with a road tractor informing a so-called 18-wheeler). The illustrated cargo transport 18 isan enclosed semi-trailer having a load floor for receiving andsupporting cargo for transport, front, left side, and right side wallsextending upward from the load floor, a roof extending over the loadfloor, and a rear opening selectively closable by one or more doors (notshown). The cargo transport 18 can have a length of 53 feet, althoughthe cargo transport 18 can have a length greater than or less than 53feet in other constructions. Aspects of the invention may not be limitedto enclosed semi-trailers as illustrated, and it will be understood thatfeatures described herein may also apply to many other types of cargotransports. The cargo transport 18 has a rear frame 20 including a rearbolster 24, a pair of vertical posts 26, and an upper cross member 30.The vertical posts 26 are laterally spaced to define a width W of therear frame 20. The rear bolster 24 spans between the vertical posts 26at their lower ends. The upper cross member 30 spans between thevertical posts 26 at their upper ends, generally parallel to and abovethe rear bolster 24. A rear cargo opening into the cargo volume of thecargo transport 18 is defined by the rear frame 20. The door(s) can besupported on the rear frame 20. The rear bolster 24 can be positioned atthe bottom rear edge of the cargo area and a bottom rear edge of therear frame 20. The character F indicates the forward direction, and thecharacter R indicates the rearward direction. Longitudinal bottom rails28 extend forwardly from the rear bolster 24 along the length of thecargo transport 18. The vertical posts 26 can have a hollow boxstructure, or other suitable construction. Opposing lateral distal endsof the rear bolster 24 are secured to (e.g., welded to) the verticalposts 26, for example at the bottom ends of the respective verticalposts 26.

The rear bolster 24 can be constructed as a stamped article, “astamping,” and particularly a sheet metal stamping. The rear bolster 24can be stamped into shape, e.g., the final shape as shown in FIGS. 1-4 ,from a single flat metal sheet. The metal sheet can be a monolithicmetal sheet having a uniform material thickness throughout (e.g.,between ⅛ inch and ¼ inch, such as 8-gauge, or 11/64 inch). Exemplarymaterials include stainless steel, aluminum, among others. At each ofthe outboard ends of the rear bolster 24, there are provided multipletaillight mounts 34, which are shown as a group of two apertures, thougheach group may be provided with different numbers, such as three. Thetaillight mounts 34 are provided in a rear-facing base surface 36 of therear bolster 24 that lies predominantly in a vertical plane P (FIG. 2 ).The rear bolster 24 includes additional surfaces or panels 37A-37E bentforwardly from the rear-facing base surface 36. For example, in end view(FIG. 2 ) it can be seen that the upper side of the rear bolster 24includes: a first horizontal panel 37A extending forwardly from a top ofthe base surface 36, a first vertical panel 37B extending downwardlyfrom the first horizontal panel 37A, a second horizontal panel 37Cextending forwardly from the first vertical panel 37B, and a secondvertical panel 37D extending downwardly from the second horizontal panel37C. As illustrated, the rear bolster 24 terminates at a bottom edge ofthe second vertical panel 37D. An additional horizontal panel 37Eextends forwardly from a bottom of the base surface 36. FIGS. 5 and 6illustrate the rear bolster 24 prior to final forming, in a state wherethe additional panels 37A-37E are not yet put into place. Rather thematerial to form the additional panels 37A-37E lies in-plane with thebase surface 36.

Furthermore, a relief 38 is stamped, or in other words pressed orembossed, into the base surface 36 to protrude therefrom. The relief 38is raised from the base surface 36 in the rearward direction R as shown,and may generally be referred to as a dock impact or engagementfeature(s). The relief 38 includes a relief portion 38A at each outboardend at least partially surrounding (e.g., above and/or below) therespective taillight mounts 34 (and the requisite taillights, oncemounted). Each outboard relief portion 38A has a horizontally-extendingyoke or fork shape in which upper and lower linear portions jointogether at an inboard side of the taillight mounts 34. The outerprofile of the fork shape in each outboard relief portion 38A where thelinear portions come together can define a constant or variable radiusR1 (i.e., four separate radiused portions in total). In some aspects,the radius R1 is between 5 and 7 inches. In addition, the two outboardrelief portions 38A can be connected to each other by a relief portion38B in the form of a horizontally-extending channel, bar, or beam. Thus,as illustrated, the various relief portions 38A, 38B are formed as anintegral stamped relief 38 in the rear bolster 24. However, thecross-sections of the various relief portions 38A, 38B are notnecessarily uniform.

As shown in the end view of FIG. 2 , the central relief portion 38Bbetween the outboard relief portions 38A extends further rearward fromthe plane P defined by the base surface 36. Particularly, and withfurther reference to the cross-sections of FIGS. 7 and 8 , the centralrelief portion 38B defines a first fore-aft depth D1 from the plane Pand the outboard relief portions 38A define a second lesser fore-aftdepth D2 from the plane P. As such, the central relief portion 38Bbetween the outboard relief portions 38A may exclusively make contactwith a loading dock structure of a building, or may limit the amount ofcontact between the loading dock structure and the outboard reliefportions 38A. This can protect the outboard relief portions 38A fromdamage, particularly when a trailer's front end is hoisted up and/or letdown while the rear bolster 24 is pressed into contact with the loadingdock structure. The central relief portion 38B may extend furtherrearward than the outboard relief portions 38A by at least 0.40 inch (10mm), and in some constructions at least 0.80 inch (20 mm) (e.g., lessthan 2 inches, in other words up to but not exceeding 50 mm). Theoutboard relief portions 38A may be raised from the base surface 36 suchthat the depth D2 is 1.0 inch (25 mm) or more (e.g., 1.4 to 1.6 inches(35 to 41 mm)). The central relief portion 38B may be raised from thebase surface 36 such that the depth D1 is at least 1.6 inches (40 mm)(e.g., 1.6 to 2.4 inches (40 to 61 mm)).

As shown in FIG. 7 , the central relief portion 38B can have a flat landsurface 44. The flat land surface of the central relief portion 38B canbe a vertically oriented surface having a height H of 0.80 inch (20 mm)or more. In cross-section, the central relief portion 38B can begenerally trapezoidal. For example, wall sections extending (e.g.,extending straight) from the base surface 36 to the flat land surface 44can be tapered to reduce in height toward the flat land surface 44. Onthe other hand, the outboard relief portions 38A can have a radius ofcurvature R2, without flat lands, at their rearward extents. The radiusR2, which can be constant or variable, is between 0.2 and 0.5 inches (5to 13 mm) in some constructions. The radius R2 can assist in easingsliding along a surface of a loading dock structure.

By stamping the relief 38 into the rear bolster 24, substantial weldinglabor is avoided. The relief 38, and other portions of the rear bolster24, can be designed for handling the loading requirements of the rearframe 20, such as rear and side impact load requirements, fork liftdrive-over loading, without weld-on reinforcements. Stressconcentrations can be avoided by rounded corners and transitions. Forexample, each outboard relief 38A has the general shape of a horseshoe,open toward the outboard end, and having a rounded, closed end oppositethereof. As such, the relief 38 as a whole has a double-forked shaped,spanning the width W of the rear bolster 24. As described above, a forkshape is formed at each location where the upper and lower parts of oneof the outboard relief portion 38A merge into the central relief portion38B.

In some constructions, an additional backing plate 142 (FIG. 9 ) isprovided on the forward side of the rear bolster 24. The backing plate142 can have a flat sheet or plate construction. The backing plate 142can lie directly behind the central relief portion 38B when viewed fromthe rear side. The backing plate 142 can cover all or a portion of thecentral relief portion 38B. In addition, the backing plate 142 may coverat least a portion of each of the outboard relief portions 38A. As shownin FIG. 9 , the outboard ends 142A of the backing plate 142 can befork-shaped and can be wider in the vertical direction than the centralportion 142B. The ends 142A can terminate at the respective taillightmounts 34. Additional gusseting may also be provided to reinforce thestamped rear bolster 24. For example, one or more gussets 146 areprovided to span between the panels 37D and 37E of the rear bolster 24.The gusset(s) 146 and/or the backing plate 142 may be attached to therear bolster stamping by welding at one or more individual locations.Although shown together, the gusset(s) 146 and the backing plate 142 maybe used separately without the other in other constructions. Even if thebacking plate 142 and/or gusset(s) 146 are utilized, so that the rearbolster is assembled from more than a single unitary, monolithic sheet,there are no reinforcing structures added to the rear bolster stampingon the rear-facing side (e.g., on the base surface 36).

The embodiments described above and illustrated in the figures arepresented by way of example only and are not intended as a limitationupon the concepts and principles of the present invention. As such, itwill be appreciated by one having ordinary skill in the art that variouschanges in the elements and their configuration and arrangement arepossible without departing from the spirit and scope of the presentinvention as set forth in the appended claims. For example, one havingordinary skill in the art will appreciate that specific features of thenumerous embodiments disclosed may be mixed and matched in other wayswhere not specifically inhibited, even though specific illustration ofsuch embodiments may not be exhaustively covered herein.

What is claimed is:
 1. A cargo transport rear frame defining a rearcargo opening, the cargo transport rear frame comprising: a pair ofposts spaced apart in a width direction, each of the pair of postsextending in a height direction; an upper cross member extending alongthe width direction between respective upper ends of the pair of posts;and a rear bolster extending along the width direction betweenrespective lower ends of the pair of posts such that the rear bolster isspaced below the upper cross member in the height direction, wherein thepair of posts, the upper cross member, and the rear bolster bound therear cargo opening, wherein the rear bolster has a first side facing ina forward direction that is perpendicular to both the width and heightdirections, and the rear bolster has a second side facing in a rearwarddirection to be exposed to a rear side of the cargo transport rearframe, wherein the rear bolster comprises a sheet metal stampingincluding a base surface and a relief embossed in the rearward directionfrom the base surface to form a loading dock engagement featureconfigured to withstand repeated loading dock impacts, wherein theloading dock engagement feature includes taillight surround portionsextending at least partially around taillight mounts at outboard ends ofthe rear bolster in the width direction, wherein the embossed relieffurther includes an additional central connecting portion extendingbetween the taillight surround portion, and wherein the centralconnecting portion is extended farther in the rearward direction thanthe taillight surround portions.
 2. The cargo transport rear frame ofclaim 1, wherein the stamping is from a single monolithic sheet ofmetal.
 3. The cargo transport rear frame of claim 1, wherein the centralconnecting portion is extended farther in the rearward direction thanthe taillight surround portions by at least 10 mm and not more than 50mm.
 4. The cargo transport rear frame of claim 3, wherein the centralconnecting portion is extended farther in the rearward direction thanthe taillight surround portions by at least 20 mm.
 5. The cargotransport rear frame of claim 1, wherein each of the taillight surroundportions has a curved rear end profile in cross-section takenperpendicular to the width direction.
 6. The cargo transport rear frameof claim 1, wherein the rear bolster further comprises a backing plateformed separately from the sheet metal stamping having the embossedrelief, the backing plate providing a reinforcement along the first sidethat covers at least a portion of the embossed relief.
 7. A rear bolsterfor a cargo transport rear frame, the rear bolster comprising: a sheetmetal stamping including: a base surface having lateral outboard endsspaced in a width direction and having a top edge and a bottom edgespaced in a height direction; a first side facing in a forward directionthat is perpendicular to both the width and height directions; a secondside facing in a rearward direction to be exposed to a rear side of thecargo transport rear frame having the rear bolster; and a reliefembossed in the rearward direction from the base surface to form aloading dock engagement feature configured to withstand repeated loadingdock impacts, wherein the loading dock engagement features includestaillight surround portions extending at least partially aroundtaillight mounts at outboard ends of the rear bolster in the widthdirection, wherein the embossed relief further includes a centralportion extending between the taillight surround portion, and whereinthe central portion is extended farther in the rearward direction thanthe taillight surround portions.
 8. The rear bolster of claim 7, whereinthe central portion and the taillight surround portions are formedcontinuous.
 9. The rear bolster of claim 7, wherein the central portionis extended farther in the rearward direction than the taillightsurround portions by at least 10 mm and not more than 50 mm.
 10. Therear bolster of claim 7, wherein the central portion is extended fartherin the rearward direction than the taillight surround portions by atleast 20 mm.
 11. The rear bolster of claim 7, wherein in each of thetaillight surround portions, the embossed relief has a curved rear endprofile in cross-section taken perpendicular to the width direction. 12.The rear bolster of claim 7, further including an additional panel bentin the forward direction from the top edge or the bottom edge.
 13. Therear bolster of claim 7, wherein the rear bolster further comprises abacking plate formed separately from the sheet metal stamping having theembossed relief, the backing plate providing a reinforcement along thefirst side that covers at least a portion of the embossed relief.
 14. Arear bolster for a cargo transport rear frame, the rear bolstercomprising: a sheet metal stamping including: a base surface havinglateral outboard ends spaced in a width direction and having a top edgeand a bottom edge spaced in a height direction; a first side facing in aforward direction that is perpendicular to both the width and heightdirections; a second side facing in a rearward direction to be exposedto a rear side of the cargo transport rear frame having the rearbolster; a relief embossed in the rearward direction from the basesurface to form taillight surround portions configured to withstandrepeated loading dock impacts.